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Search Results: 1 - 10 of 1704 matches for " Susanne Deininger "
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In Vitro and In Vivo Antimalarial Activity Assays of Seeds from Balanites aegyptiaca: Compounds of the Extract Show Growth Inhibition and Activity against Plasmodial Aminopeptidase
Peter Kusch,Susanne Deininger,Sabine Specht,Rudeka Maniako,Stefanie Haubrich,Tanja Pommerening,Paul Kong Thoo Lin,Achim Hoerauf,Annette Kaiser
Journal of Parasitology Research , 2011, DOI: 10.1155/2011/368692
Abstract: Balanites aegyptiaca (Balanitaceae) is a widely grown desert plant with multiuse potential. In the present paper, a crude extract from B. aegyptiaca seeds equivalent to a ratio of 1?:?2000 seeds to the extract was screened for antiplasmodial activity. The determined IC50 value for the chloroquine-susceptible Plasmodium falciparum NF54 strain was 68.26? . Analysis of the extract by gas chromatography-mass spectrometry detected 6-phenyl-2(H)-1,2,4-triazin-5-one oxime, an inhibitor of the parasitic M18 Aspartyl Aminopeptidase as one of the compounds which is responsible for the in vitro antiplasmodial activity. The crude plant extract had a of 2.35? and showed a dose-dependent response. After depletion of the compound, a significantly lower inhibition was determined with a of 4.8? . Moreover, two phenolic compounds, that is, 2,6-di-tert-butyl-phenol and 2,4-di-tert-butyl-phenol, with determined IC50 values of 50.29? and 47.82? , respectively, were detected. These compounds may contribute to the in vitro antimalarial activity due to their antioxidative properties. In an in vivo experiment, treatment of BALB/c mice with the aqueous Balanite extract did not lead to eradication of the parasites, although a reduced parasitemia at day 12 p.i. was observed. 1. Introduction Traditional medicine is still the first point of healthcare for many people in sub-Saharan Africa, where there has been a long and rich tradition of obtaining treatments from herbs and trees. In the case of malaria, Africa’s traditional healers use hundreds of indigenous plants for remedies. Until the 1950s, when synthetic chemistry began to dominate drug research and development (R and D) efforts, most drugs developed and registered in the pharmacopoeia were in fact based on natural products. Plant alkaloids, quinine among them, were the first components of natural herbal remedies to be extracted and refined for more effective use in the early 19th century. Some 150 years later, quinine is still used as front-line therapy for severe malaria, even if it is not the recommended drug for this use when artemisinin combination therapies (ACTs) are available. In this context, it seems to be quite surprising that no African lead has emerged so far. Meanwhile, there are efforts to assess plant remedies against malaria for their application in health care systems [1]. B. aegyptiaca (L.) (Balanitaceae) is a woody tree growing in various ecological conditions (from 100?mm to 1000?mm annual rainfall), but mainly distributed in semiarid and arid zones in tropical Africa [2]. This tree reaches 10?m (33?ft)
Alu elements: know the SINEs
Prescott Deininger
Genome Biology , 2011, DOI: 10.1186/gb-2011-12-12-236
Abstract: Alu elements represent one of the most successful of all mobile elements, having a copy number well in excess of 1 million copies in the human genome [1] (contributing almost 11% of the human genome). They belong to a class of retroelements termed SINEs (short interspersed elements) and are primate specific. These elements are non-autonomous, in that they acquire trans-acting factors for their amplification from the only active family of autonomous human retroelements: LINE-1 [2].Although active at higher levels earlier in primate evolution, Alu elements continue to insert in modern humans, including somatic insertion events, creating genetic diversity and contributing to disease through insertional mutagenesis. They are also a major factor contributing to non-allelic homologous recombination events causing copy number variation and disease. Alu elements code for low levels of RNA polymerase III transcribed RNAs that contribute to retrotransposition. However, the ubiquitous presence of Alu elements throughout the human genome has led to their presence in a large number of genes and their transcripts. Many individual Alu elements have wide-ranging influences on gene expression, including influences on polyadenylation [3,4], splicing [5-7] and ADAR (adenosine deaminase that acts on RNA) editing [8-10].This review focuses heavily on studies generated as a result of the advent of high-throughput genomics providing huge datasets of genome sequences, and data on gene expression and epigenetics. These data provide tremendous insight into the role of Alu elements in genetic instability and genome evolution, as well as their many impacts on expression of the genes in their vicinity. These roles then influence normal cellular health and function, as well as having a broad array of impacts on human health.The general structure of an Alu element is presented in Figure 1a. The body of the Alu element is about 280 bases in length, formed from two diverged dimers, ancestrally deri
The Physiological Response during Divergent Thinking  [PDF]
Gareth H. Loudon, Gina M. Deininger
Journal of Behavioral and Brain Science (JBBS) , 2016, DOI: 10.4236/jbbs.2016.61004
Abstract: Our research studied the physiological response of participants during a creative task to investigate if a person’s psychophysiological state was correlated with divergent thinking performance. We used heart rate variability as our physiological measure. We asked 50 participants to perform a cognitive task that assessed their divergent thinking skills and recorded their heart rate and heart rate variability (HRV) before and during the task. Frequency domain analysis was performed on the HRV. The results showed that there was a significant negative correlation between log-transformed low frequency HRV power and the number of “divergent thinking” words generated. Our results suggest that a person’s psychophysiological state is correlated with their divergent thinking performance, and that attention and motivation may be important factors, however this needs further research. Our findings also suggest that being in a relaxed state before the start of a creative task is not a predictor of creative performance.
The Physiological Response to Drawing and Its Relation to Attention and Relaxation  [PDF]
Gareth H. Loudon, Gina M. Deininger
Journal of Behavioral and Brain Science (JBBS) , 2017, DOI: 10.4236/jbbs.2017.73011
Abstract: The main purpose of this study was to analyze the physiological response of participants during a creative activity and compare the results to their physiological response during states of high attention and relaxation. Our interest was not only about the relationship between creativity and attention, but also about the role of valence and arousal. We used heart rate variability (HRV) as our physiological measure. We asked twenty-two participants to undertake three activities: a stroop test; a relaxation activity; and a drawing activity. After each activity, the participants were asked to reflect on their levels of attention, relaxation and enjoyment. The results showed significant physiological differences between the three activities: mean heart rate, F(2, 42) = 8.96, p = 0.001; log-transformed low frequency HRV power, F(1.43, 30.07) = 18.12, p < 0.001; and log-transformed high frequency HRV power, F(2, 42) = 6.25, p = 0.004. Overall, the results suggested that participants had high levels of attention during the drawing activity, with positive valence. The results also suggested that participants’ levels of arousal differed between the three activities. The implications of these results are described in the discussion.
A teoria econ mica dos Estados antigos: a quest o do capitalismo na Antiguidade na vis o de Weber Economic theory of the ancient States: Weber's view of the question of capitalism in Antiquity
Jürgen Deininger
Tempo Social , 2012, DOI: 10.1590/s0103-20702012000100004
Abstract: O artigo discute o problema do capitalismo na Antiguidade, tal como Max Weber o formulou. Trata, portanto, de reconstruir o entendimento de Weber desse fen meno, ou seja, das formas de organiza o econ mica na Antiguidade. A análise do texto de Weber de 1908, "Agrarverh ltnissen im Altertum" [Rela es agrárias na Antiguidade], oferece a base de toda a discuss o; mas também s o abordados o contexto intelectual da problematiza o de Weber, como a polêmica Meyer-Bücher acerca dos fundamentos da economia antiga, assim como aspectos específicos do capitalismo antigo, no entender de Weber, em que a rela o com a dimens o política ocupa papel de destaque. The article discusses the problem of capitalism in Antiquity, as formulated by Max Weber. It seeks to reconstruct Weber's understanding of the phenomenon, that is, the forms of economic organization in Antiquity. An analysis of Weber's 1908 text "Agrarverh ltnissen im Altertum" [Agrarian relations in Antiquity] provides the basis for the discussion as a whole. However the article also examines the intellectual context of Weber's problematization, such as the Meyer-Bücher polemic concerning the fundamental aspects of the ancient economy, as well as specific aspects of ancient capitalism, as Weber understood them, where the relation with the political dimension assumes a prominent role.
Distinct Roles for FOXP3+ and FOXP3? CD4+ T Cells in Regulating Cellular Immunity to Uncomplicated and Severe Plasmodium falciparum Malaria
Michael Walther ,David Jeffries,Olivia C. Finney,Madi Njie,Augustine Ebonyi,Susanne Deininger,Emma Lawrence,Alfred Ngwa-Amambua,Shamanthi Jayasooriya,Ian H. Cheeseman,Natalia Gomez-Escobar,Joseph Okebe,David J. Conway,Eleanor M. Riley
PLOS Pathogens , 2009, DOI: 10.1371/journal.ppat.1000364
Abstract: Failure to establish an appropriate balance between pro- and anti-inflammatory immune responses is believed to contribute to pathogenesis of severe malaria. To determine whether this balance is maintained by classical regulatory T cells (CD4+ FOXP3+ CD127?/low; Tregs) we compared cellular responses between Gambian children (n = 124) with severe Plasmodium falciparum malaria or uncomplicated malaria infections. Although no significant differences in Treg numbers or function were observed between the groups, Treg activity during acute disease was inversely correlated with malaria-specific memory responses detectable 28 days later. Thus, while Tregs may not regulate acute malarial inflammation, they may limit memory responses to levels that subsequently facilitate parasite clearance without causing immunopathology. Importantly, we identified a population of FOXP3?, CD45RO+ CD4+ T cells which coproduce IL-10 and IFN-γ. These cells are more prevalent in children with uncomplicated malaria than in those with severe disease, suggesting that they may be the regulators of acute malarial inflammation.
Elevated Adaptive Immune Responses Are Associated with Latent Infections of Wuchereria bancrofti
Kathrin Arndts equal contributor,Susanne Deininger equal contributor,Sabine Specht,Ute Klarmann,Sabine Mand,Tomabu Adjobimey,Alexander Y. Debrah,Linda Batsa,Alexander Kwarteng,Christian Epp,Mark Taylor,Ohene Adjei,Laura E. Layland ? ,Achim Hoerauf ?
PLOS Neglected Tropical Diseases , 2012, DOI: 10.1371/journal.pntd.0001611
Abstract: In order to guarantee the fulfillment of their complex lifecycle, adult filarial nematodes release millions of microfilariae (MF), which are taken up by mosquito vectors. The current strategy to eliminate lymphatic filariasis as a public health problem focuses upon interrupting this transmission through annual mass drug administration (MDA). It remains unclear however, how many rounds of MDA are required to achieve low enough levels of MF to cease transmission. Interestingly, with the development of further diagnostic tools a relatively neglected cohort of asymptomatic (non-lymphedema) amicrofilaremic (latent) individuals has become apparent. Indeed, epidemiological studies have suggested that there are equal numbers of patent (MF+) and latent individuals. Since the latter represent a roadblock for transmission, we studied differences in immune responses of infected asymptomatic male individuals (n = 159) presenting either patent (n = 92 MF+) or latent (n = 67 MF?) manifestations of Wuchereria bancrofti. These individuals were selected on the basis of MF, circulating filarial antigen in plasma and detectable worm nests. Immunological profiles of either Th1/Th17, Th2, regulatory or innate responses were determined after stimulation of freshly isolated PBMCs with either filarial-specific extract or bystander stimuli. In addition, levels of total and filarial-specific antibodies, both IgG subclasses and IgE, were ascertained from plasma. Results from these individuals were compared with those from 22 healthy volunteers from the same endemic area. Interestingly, we observed that in contrast to MF+ patients, latent infected individuals had lower numbers of worm nests and increased adaptive immune responses including antigen-specific IL-5. These data highlight the immunosuppressive status of MF+ individuals, regardless of age or clinical hydrocele and reveal immunological profiles associated with latency and immune-mediated suppression of parasite transmission.
HMOX1 Gene Promoter Alleles and High HO-1 Levels Are Associated with Severe Malaria in Gambian Children
Michael Walther ,Adam De Caul,Peter Aka,Madi Njie,Alfred Amambua-Ngwa,Brigitte Walther,Irene M. Predazzi,Aubrey Cunnington,Susanne Deininger,Ebako N. Takem,Augustine Ebonyi,Sebastian Weis,Robert Walton,Sarah Rowland-Jones,Giorgio Sirugo,Scott M. Williams,David J. Conway
PLOS Pathogens , 2012, DOI: 10.1371/journal.ppat.1002579
Abstract: Heme oxygenase 1 (HO-1) is an essential enzyme induced by heme and multiple stimuli associated with critical illness. In humans, polymorphisms in the HMOX1 gene promoter may influence the magnitude of HO-1 expression. In many diseases including murine malaria, HO-1 induction produces protective anti-inflammatory effects, but observations from patients suggest these may be limited to a narrow range of HO-1 induction, prompting us to investigate the role of HO-1 in malaria infection. In 307 Gambian children with either severe or uncomplicated P. falciparum malaria, we characterized the associations of HMOX1 promoter polymorphisms, HMOX1 mRNA inducibility, HO-1 protein levels in leucocytes (flow cytometry), and plasma (ELISA) with disease severity. The (GT)n repeat polymorphism in the HMOX1 promoter was associated with HMOX1 mRNA expression in white blood cells in vitro, and with severe disease and death, while high HO-1 levels were associated with severe disease. Neutrophils were the main HO-1-expressing cells in peripheral blood, and HMOX1 mRNA expression was upregulated by heme-moieties of lysed erythrocytes. We provide mechanistic evidence that induction of HMOX1 expression in neutrophils potentiates the respiratory burst, and propose this may be part of the causal pathway explaining the association between short (GT)n repeats and increased disease severity in malaria and other critical illnesses. Our findings suggest a genetic predisposition to higher levels of HO-1 is associated with severe illness, and enhances the neutrophil burst leading to oxidative damage of endothelial cells. These add important information to the discussion about possible therapeutic manipulation of HO-1 in critically ill patients.
The Relationship between Institutional Efficiency and Instructional Quality in Higher Education  [PDF]
Susanne Rassouli-Currier
Creative Education (CE) , 2012, DOI: 10.4236/ce.2012.32035
Abstract: Wage setting methodologies for university faculty may be merit/market based or administered. Failure to exploit the fact that faculty productivity depends on abilities and wages results in inefficient use of university budgets. If such inefficiencies exist it suggests suboptimal productivity of the existing faculty and the inability to attract new qualified faculty. As motivation for this analysis, a simple model of university faculty “output” maximization is presented. Efficient budget allocation requires that faculty compensation be structured so that marginal productivities are equated across faculty. This paper examines and compares the efficiency of several regional universities in the US, identified as “peers”, employing the Data Envelopment Analysis (DEA) estimation method. The results suggest the existence of inefficiencies and more notably, that the homogeneity assumption regarding the peers is questionable.
Impact of a Practical Skills Assessment on the Individual Engagement of Undergraduate Pharmacy Students within Laboratory Coursework Sessions  [PDF]
Susanne P. Boyle
Creative Education (CE) , 2012, DOI: 10.4236/ce.2012.326137
Abstract: This study reports on the learner impact, practicability and cost effectiveness of an individual practical skills test designed to assess the interpretative and manipulative skills of undergraduate pharmacy in a laboratory setting. The reliability of the assessment tool across a 5 year period was examined and refinements introduced in response to constructive feedback from colleagues and learner feedback recorded via end of year Student Evaluation Questionnaires. A blended learning strategy supported the needs of multiple learning styles and inclusion of a formative assessment increased student confidence and improved cohort performance in the summative assessment. Future directions include the introduction of a peer learning activity as a means of reducing group sizes and providing an opportunity for the learners to develop skills in constructive critique and reflective learning.
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